US3080429A - Preparation of halocareon having the empirical formula c10cl4f14 - Google Patents

Description

a assua e 3Q i atented Mar. 1953 tastes Fats r It is understood that there are other possible routes 37!}34J942g by which the final product can be attained, as for ex- PREPAR THQN (9F HALGKIARBGN HAWNG Tim ample, wherein the addition of the first two fluorine atoms ENWHHCAL FQRMULA 14 to the starting material in Equation H is illustrated as at Charles Bamnauckas and Samuel Gamma Niagara 5 1,2-addition to a terminal double bond of a triene sys- I 7' u ggg zgg igfi g if gfggz gfig fifikgfiggs tem, it is also possible to have a 1,2-add1t1on to the middle N b m Ffl zzg 1957, s N0. 99 519 double bond of the triene system. In addition it is also 1 Claim. (Ci. 260-648) possible to have a 1,4-addition across conjugated double bonds of the triene system. Thus it is possible to illustrate This invention relates to a new and useful chemical 10 the chemical processes involved in Equations 11 through compound composed of carbon, chlorine and fluorine, i.e(i IV by the following general equation:

a halocarbon havin an em irical formula 0 01 33 an w a distillation range of abofit 220 to 235 degrees centi- (V) c1C14F8+6C0F3 )(?mC14114 lcorz grade. To those skilled in the art it is obvious that there are a The compound of this invention may b prepared b 15 number of stereoisomers theoretically possible for the fiuorinating a halocarbon compound having an empirical CIOCLLFM this f formula C ChF and a melting point of about 74 to 75 The Startms mammal, CC14F8, and cobalt trrfluoude degrees centigrade with cobalt trifiuoride at an elevated are mixed and heated o an elem/ted pe Wheretemperature, and recovering the C CLQF so produced. in the brown C0ba1t mflu011de h In Q In preparing the product of thi in enti n, presumably 2o brown to pink. Additional quantities of cobalt trifluoride one of the paths that the reaction can take is illustrated are added until such tlme there f 9 change in accordance with the following equations; from brown to pink or untll the reaction mixture becomes difiicult to agitate because of the high percentage of solids present. The spent cobalt salts are removed (I) by filtration followed by subsequent extraction with carbon tetrachloride and recovery of the organic from the carbon tetrachloride extract. The filtrate and the rel l covered material from the carbon tetrachloride extract are 01 combined and retreated with cobalt trifluoride until the r fluorinating agent fails to turn in color from brown to pink. The recovered product from the reaction mixture is a colorless oil and is neutralized to remove small amounts of acidic impurities that could develop during the fluorination step. The fiuorination procedure is best in Ft F2 carried out in the absence of a solvent.

The product of this invention is highly soluble in dip fip, methyl silicone fluids over a broad temperature range of 200% about 60 to 420 degrees Fahrenheit. In addition the O1 incorporation of C ChF into dimethyl silicones (Dow- Fz Coming 200 fluid with a viscosity of centistokes at l I 25 degrees centigrade) as an equal component improves F the anti-wear properties of the silicone oil to the point 29F? that it is equivalent to that of a synthetic lubricant, such L as di-Z-ethylhexyl sebacate. It is well known in the art that di-Z-ethylhexyl sebacate is used frequently as a base stock in synthetic lubricants.

Prior to the invention of this product it was well known in the art that chlorofiuoro compounds impart anti-wear characteristics to silicone oils. The use of chlorofiuoro 50 compounds for this purpose has been hindered due to the fact that products that were highly soluble in the silicones at low temperatures were of such a low molecular weight that the mixtures could not be used at elevated temperatures. Chlorofiuorocarbons that have boiling points high enough to permit use of the oils at elevated temperatures were not soluble enough at sub-zero ternperatures to retain a single phase fluid. C Cl F overcomes both of the difiiculties in one product, namely, it has excellent solubility characteristics over the temperature range of degrees Fahrenheit to above 420 degrees Fahrenheit. In addition its distilling range is such that it will not readily volatilize from the mixture at elevated temperatures.

Silicone oils in general have what are considered to be excellent Viscosity characteristics and chlorofiuorocarbons in general are considered to have poor viscosity characteristics as compared to silicones. One common method of expressing viscosity characteristics of a hydraulic fluid or lubricant is to report the ASTM slope over the temperature range of degrees Fahrenheit to 210 degrees Fahrenheit. The following table illustrates the fact that the addition of C Cl F even to the extent (IV) F2 60 of 50 percent does not markedly affect the of the silicon.

viscosity slope Base fluid: ASTM slope 100 F. to 210 F. Di-Z-ethylhexyl sebacate 0.702 Dimethyl silicone (Dow-Corning 200 fluid 50 centistokes at 25 C.) 0.585 50% C Cl F :50% dimethyl silicone 0.606 (3190141 14 It should be noted that the silicone lowers the viscosity slope of the C Cl F fluid to a considerable degree. This represents a highly desirable improvement.

C ChF is a non-reactive material that can be subjected to prolonged exposure to a variety of chemicals such as chlorine, hydrogen fluoride, nitric acid, chlorosulfonic acid, fluorosulfonic acid, hydrogen chloride, oxygen and chlorine oxides without any deleterious effect. This resistance to chemical attack along with the wide liquid range of the product coupled with its viscosity characteristics at low temperatures makes this an ideal fluid for gages and metering devices handling these re active chemicals.

The process for the preparation of the starting material used in the preparation of the product of this invention is fully illustrated in Example II given hereinafter. The material is disclosed and claimed in a copending application S.N. 699,438, filed of even date herewith, now US. Patent No. 2,951,097, in the name of Samuel Gelfand.

The following examples illustrate methods for the preparation and utility of the compound of this invention; however, they are not to be construed as limiting except as defined in the appended claims.

EXAMPLE I Preparation C ChF (1,200 grams) prepared as in Example 11 was charged into a two liter, three-necked round bottom flask equipped with a sealed stirrer, a thermometer, a reflux condenser and heating and/ or cooling means. Fifty grams of cobalt trifluoride was added to the reactor and the reaction mixture was heated to 170 to 180 degrees centigrade at which point the cobalt salts changed in color from brown to pink. The mixture was cooled to 120 degrees centigrade, an additional 50 grams of cobalt trifluoride was added, and the resultant mixture was heated to 170 to 180 degrees centigrade. This procedure was repeated until a total of 1600 grams of cobalt trifluoride had been added. At this stage the reaction was not complete, but the reaction mixture contained such a high percent of solids that agitation became ineflieient. As a result the reaction mixture after cooling was filtered and the filter cake was extracted twice with hot carbon tetrachloride to recover organic reactant and products. After distillation of the carbon tetrachloride extracts, the recovered C Cl F and fluorination products were combined with the filtrate from the reaction mixture (total 1250 grams) and fluorinated as before with an additional 500 grams of cobalt trifluoride. The last cobalt trifluoride did not change from the brown color, this being an indication that the reaction had gone to completion. The organic products were recovered from the reaction mixture in the manner described above, and there was obtained 1200 grams of a colorless oil. This oil was neutralized by stirring with anhydrous sodium carbonate and filtering. The liquid recovered was analyzed and found to distill over a range of about 220 to 235 degrees centigrade and to have a chlorine content of 26.71 percent by weight, a molecular weight of 516 which corresponds to C Cl F having a chlorine content of 26.9 percent by weight, and a molecular weight of 523 respectively.

EXAMPLE 11 Ten moles (2780 grams) of 1,2,3,3-tetrachlorotetrafluorocyclopentene and 370 grams of copper powder were charged into a five liter, three-necked round bottom flask equipped with a sealed stirrer, a thermometer, a reflux condenser and heating and/or cooling means. The reactants were heated to a reflux temperature of about 154 degrees centigrade while maintaining eificient agitation. While the reaction mixture was maintained at reflux by heating, the reaction was continued, with periodic addition of copper powder until a total of 1370 grams had been added. As the reaction proceeded the temperature of the reaction mixture in the liquid phase rose from about 150 degrees centigrade until a final temperature of about 185 degrees centigrade was reached. Thereafter, the reaction mixture was filtered with the major portion of the product being in the filtrate. The residual cake of copper and copper chlorides was extracted twice with hot carbon tetrachloride to recover absorbed starting material and product and the extract was distilled to remove the carbon tetrachloride. The residue from the distillation of the carbon tetrachloride extraction mixture was combined with the filtrate from the reaction mixture and was distilled, to recover unreacted starting material and to isolate the product. An percent yield of a colorless to pale yellow liquid (1218 grams, 3.0 moles) having a boiling point of about degrees centigrade at 1 mm., was obtained. The product solidified on standing. After two recrystallizations from ethanol, colorless needles were obtained, analyzed, and found to possess a melting point range of 74 to 75 degrees centigrade, a chlorine content of 34.5 percent by weight, which corresponds to C ChF having a theoretical chlorine content of 34.3 percent by weight. The infrared spectrum showed absorption characteristic of C=C double bonds at 6.45a. The ultraviolet spectrum showed peaks at 285,296 ma, e =41,300.

EXAMPLE III A formulation for a base fluid for hydraulic and lubricant applications was prepared containing 50 percent by weight of the compound C Cl F from Example I and 50 percent by weight of a dimethyl silicone oil (Dow- Corning Silicone 200 fluid with a viscosity of 50 centistokes at 25 degrees centigrade) and was tested in a Shell Four-Ball Tester to determine its wear characteristics. A description of the Shell Four-Ball Tester is disclosed in U.S. Patent 2,019,948. The results of the test are compared in the following table with test data obtained on stock Dow-Corning Silicone 200 fluid with a viscosity of 50 centistokes at 25 degrees centigrade and on a typical dibasic acid ester such as di-Z-ethylhexyl sebacate which is a base stock for synthetic lubricants.

TABLE Average Wear Scar Di- Norm-Wear tests were conducted in the Shell Four-Ball Wear Tester at 75 degrees centigrade, 620 rpm and a one-hour test time using SKF Industries grade one steel ball bearings.

These results show that a fluid consisting of 5 percent of C ChF and 50 percent of a dimethyl silicone oil (Dow-Corning Silicone 200 fluid of 50 centistoke viscosity at 25 degrees centigrade) has the wear characteristics of lubricant base fluids derived from dihasic acid esters, e.g., di-Z-ethylhexyl sebacate. From the test data it is apparent that the incorporation of the C Cl F into the formulation has imparted anti-wear properties to the silicone oil that were not present without the 0 C1 1 fluid.

C ChF has other properties that make it useful as a fluid in applications requiring a non-reactive material of wide liquid range that has a viscosity of less than 5000 centistokes at a temperature of 60 degrees Fahrenheit. The viscosity of 0 01 1 at a variety of temperatures is as follows:

C Cl F does not react with such reactive materials as chlorine, hydrogen fluoride, nitric acid, chlorosulfonic acid, fluorosulfonic acid, hydrogen chloride, oxygen and chlorine oxides. The fluid can be used in gages and metering equipment handling such chemicals. In addition it is particularly useful in the lubrication of valve stems and packings when they are in use at below zero degrees centigrade in chlorine and hydrogen chloride service.

The viscosity characteristics of C Cl F are such that it is a useful flotation agent in gyros that are required to function under arctic conditions. 0 C1 1 is also useful as an additive in other fluids as it is soluble in SAE oil at room temperature to the extent of 25 percent by Weight and is soluble in di-Z-ethylhexyl sebacate at l0 degrees centigrade to the extent of 50 percent. 25 2,668,182

This characteristic permits the raising of the flash point of flammable liquids.

It is to be understood that the invention is not limited to the specific examples which have been offered merely as illustrative and that modification may be made within the scope of the appended claim without departing from the spirit of the invention.

We claim:

The process for preparing a halocarbon having an empirical formula C Cl F and a distillation range of about 220 to 235 degrees centigrade, which comprises: fluorinating a halocarbon having the structural formula References Cited in the file of this patent UNITED STATES PATENTS 2,578,720 McBee et al. Dec. 18, 1951 2,654,789 Ligett Oct. 6, 1953 Miller Feb. 2, 1954 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,080,429 7 March 5, 1963 Charles l Baranauckas et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4, lines 50 to 59, in the TABLE, first column,

line 3 thereof, for "Silicone "200" K 50 percent" read Silicone "200" 50 percent same column 4, line 63, for

"5 percent" read 50 percent Signed and sealed this 22nd day of June 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attcsting Officer Commissioner of Patents